Construction of Jenkins sequel platform based on kubernetes/k8s (Part 2)

Jenkins master slave architecture

Installing and configuring NFS

Introduction to NFS

NFS (Network File System), its biggest function is to enable different machines and different operating systems to share files with each other through the network. We can use NFS to share Jenkins running configuration files, Maven's warehouse dependency files, etc

NFS mount

We install the NFS server on the master machine

Install services for NFS (all k8s the nodes need to be installed)

yum -y install nfs-utils

Create shared directory on master

Create a shared directory to store Jenkins' configuration files

mkdir -p /opt/nfs/jenkins

cat >> /etc/exports << 'EOF'
/opt/nfs/jenkins *(rw,no_root_squash)
EOF

Start the service and view the NFS shared directory

Start service

systemctl enable nfs --now

On three k8s machines, view the shared directory

showmount -e 192.168.23.15

Install Jenkins master in Kubernetes

Create NFS client provisioner

NFS client provisioner is a simple NFS external provisioner of Kubernetes. It does not provide NFS itself and requires existing NFS servers to provide storage.

Upload NFS client provider build file

Link: https://pan.baidu.com/s/1GIH18-iNF0m8TMiQNAxVeA?pwd=mpcw
Extraction code: mpcw

ls 
unzip nfs-client.zip 
cd nfs-client
sed -i '/192.*/ s/192.*/192.168.23.15/g'  deployment.yaml

Build pod resources of NFS client provider

cd nfs-client
kubectl apply -f .

Check whether the pod is installed successfully

kubectl get pods

Install Jenkins master

Upload Jenkins master build file

Link: https://pan.baidu.com/s/1RwioaFdgCk-tB4cEWF5ovQ?pwd=52d5
Extraction code: D525

unzip jenkins-master.zip
cd jenkins-master/
ls

There are two points to note:

First, in statefulset Yaml file, which declares the Jenkins master file storage using NFS client provider

Second, the Service publishing method adopts NodePort, which will randomly generate node access ports

Create a namespace for Kube Ops

Because we put Jenkins master's pod under Kube ops

kubectl create namespace kube-ops
kubectl get ns

Build pod resources of Jenkins master

cd jenkins-master
kubectl create -f .

View the status of the pod and the scheduling node and port

kubectl get pods -n kube-ops -o wide
kubectl  get service  -n kube-ops

Visit jenkins

Use Jenkins browser to access address

ip of the node where Jenkins is located: mapped port

192.168.23.15:32420

Get the initial password. The initial password is in the data volume directory and stored in initialAdminPassword

Set the plugin download address of Jenkins and download the plugin

cd /opt/nfs/jenkins/kube-ops-jenkins-home-jenkins-0-pvc-28d3fcd1-0a47-4da9-b93d-a9a34fa152fa/updates/

sed -i 's/http:\/\/updates.jenkins- ci.org\/download/https:\/\/mirrors.tuna.tsinghua.edu.cn\/jenkins/g' default.json && sed -i 's/http:\/\/www.google.com/https:\/\/www.baidu.com/g' default.json

Manage Plugins click Advanced and change the Update Site to the download address of domestic plug-ins

https://mirrors.tuna.tsinghua.edu.cn/jenkins/updates/update-center.json

Restart Jenkins

Install the basic plug-in first

Localization:Chinese

Git

Pipeline

Extended Choice Parameter

After installation, restart Jenkins

Integration of jenins and kubernetes

Install kubernetes plug-in

System management -- > plug-in management -- > optional plug-ins -- > kubernetes

Integration of Jenkins and Kubernetes

System management -- > system configuration -- > cloud -- > new cloud -- > kubernetes

Configure cluster information

kubernetes address adopts kube's server discovery: https://kubernetes.default.svc.cluster.local

The namespace is filled with Kube OPS, and our services are placed in this self built namespace

Then click Test Connection to test the connection

Jenkins URL: http://jenkins.kube-ops.svc.cluster.local:8080 Port 8080 comes from service Yaml file definition

Build Jenkins slave custom image

When Jenkins master builds a Job, Kubernetes will create a Pod of Jenkins slave to complete the construction of the Job. We choose the image running Jenkins slave as the official recommended image: Jenkins / JNLP Slave: latest, but there is no Maven environment in this image. For convenience, we need to customize a new image:

Copy maven package, settings configuration file and Dockerfile file to the master host

Link: https://pan.baidu.com/s/1EZ0yopDHMoaw5UHXbM1qmg?pwd=uyw2
Extraction code: uyw2

ls jenkins-slave.zip
unzip jenkins-slave.zip
cd jenkins-slave/

Dockerfile file contents are as follows:

#Based on the official image
FROM jenkins/jnlp-slave:latest

MAINTAINER itcast

# Switch to root account for operation
USER root

# Install maven
COPY apache-maven-3.6.2-bin.tar.gz .

RUN tar -zxf apache-maven-3.6.2-bin.tar.gz && \
    mv apache-maven-3.6.2 /usr/local && \
    rm -f apache-maven-3.6.2-bin.tar.gz && \
    ln -s /usr/local/apache-maven-3.6.2/bin/mvn /usr/bin/mvn && \
    ln -s /usr/local/apache-maven-3.6.2 /usr/local/apache-maven && \
    mkdir -p /usr/local/apache-maven/repo

COPY settings.xml /usr/local/apache-maven/conf/settings.xml

USER jenkins

Build an image and upload it to the image warehouse

docker build -t jenkins-slave-maven:latest .

After successful construction, a new image Jenkins slave Maven: latest is generated

docker images

Label the image and upload it to the library project of the warehouse

#First configure the address of the registered image warehouse (please restart docker)
cat /etc/docker/daemon.json

#Log in to the warehouse on the mster host first, and log in as an administrator
docker login -u admin -p Harbor12345 192.168.23.13:85

#Label the image warehouse address / project name / image name: Label
docker tag jenkins-slave-maven:latest 192.168.23.13:85/library/jenkins-slave-maven:latest

#Push to image warehouse
docker push  192.168.23.13:85/library/jenkins-slave-maven

After the push is successful, go to the library project of the image warehouse to view it

Test whether Jenkins slave can be created

Add voucher

Add the certificate of gitlab by using the user name and password

Create a new Jenkins pipeline project

Pipeline:

def git_address = "http://192.168.23.10:82/my_group/tensquare_back.git"
def git_auth = "9972329a-8a9c-4504-83bd-1ed89556f824"

//Create a Pod template with the label Jenkins slave
podTemplate(label: 'jenkins-slave', cloud: 'kubernetes', containers: [ 
    containerTemplate(
        name: 'jnlp',
        image: "192.168.23.13:85/library/jenkins-slave-maven:latest"
    )
  ]
)
{
    //Reference the pod module of Jenkins slave to build the pod of Jenkins slave 
    node("jenkins-slave"){
        stage('Pull code'){
            checkout([$class: 'GitSCM', branches: [[name: '*/master']], extensions: [], userRemoteConfigs: [[credentialsId: "${git_auth}", url: "${git_address}"]]])
        }
    }
}

Open a new Jenkins window and enter node management.

Then, click build in another window. Refresh the node management window and observe the changes

It can be seen that during the architecture period, Jenkins opened a new connection node and used the new node to build the project. After the construction, the node is deleted

On the output information of the project, you can also see that the slave node has been created